Re: O.T.- Chrome plating on salt water boat items??
Cliff
>Joe788 wrote:
>> Today I had a guy telling me that chrome does not stand up to the
>> weather and environment of a boat that is used in salt water. Now we
>> are not talking about a propeller here, but various chrome trinkets
>> around the boat, such as wakeboard racks, speaker enclosures, shifter
>> knobs, etc.
>>
>> I was under the impression that chrome was a pretty good coating for
>> such applications, but did not want to argue for fear of jamming my
>> foot in my mouth. I know this is a pretty resourceful group when it
>> comes to random bits of manufacturing related information....(remember
>> the 900 post thread about the corrosion on the Fadal toolchanger??) .
>> So, does anybody know where to find any decent online reference
>> material for chrome plating's resistance to a salt water environment? I
>> searched around on Google for a few minutes, but could not find
>> anything of relevance.
>>
>
>One suggestion is Stainless Steel. It looks much like chrome, maybe you
>saw SS instead?
http://www.chromplate.com/flash_hard_chrome.html
[
Micro-Cracked Hard Chrome (Bright)
This type of hard chrome offers a number advantages over the standard Hard
Chrome...
Harder and more wear resistant (hardness appox. 1050-1150 Vickers or 70 Rockwell
C).
Offers better corrosion protection than standard hard chrome
Brighter finish than hard chrome
These extra qualities make this mirco cracked hard chrome ideally suited for use
with hydraulic rams which may be operating in dirty environments, if dirt is
liable to lodge in seals, less harm may be done to the ram. For wet or
salt-water environments, an under coat of nickel plating provides a corrosion
resistant layer, that extends the working life of the ram considerably.
]
[
Special Note on Hard Chrome
It is a common misconception that chrome plating provides corrosion protection.
This is not the case, only slight protection is given. Hard Chrome is porous at
the microscopic level, which can let moisture and chemicals through to attack
the base material. If the item is to be used in a damp environment, or where
water based inks are used on printing machines, a layer of Nickel plating is
required, prior to hard chrome plating.
]
I'd think that any fasteners should be of the exact same surface material
(or nonconductive plastics) (to avoid electrolytic corrosion) and that
such should not be joined to other metals (or in contact with them).
I.E.: Use the same plating on any fasteners into a fiberglass boat hull,
don't even think of it with Aluminum or steel.
If this is a submerged application perhaps a sacrificial electrode
could be used as well?
--
Cliff
Guy Fawkes
yacht sector.
chrome plate - waste of time and money
galvanised - lovely stuff, but ooh, it's not shiny, yuck.
stainless (various grades) - ooh, it's shiny, personally speaking you
couldn't give me the stuff on a boat, nightmare when used with any
other metal, which it always is in practice, and breaks with little
warning, yet is still used for rigging cos it's shiny..
bronze (various grades) - shiny and most suitable, will de zinc over
time if not protected by sacrificial anodes if installed badly
aluminium - has it's uses, god help you when someone chrome plates it,
or worse still uses a stainless fastener in it, which happens all the
time
sug...@hotmail.com
on Grand Banks.
Andrew VK3BFA
am refurbishing, was planning to use stainless steel bolts and clamps
(Its all alumium construction...) - can you suggest something more
suitable?
Andrew VK3BFA.
Guy Fawkes
if "it's all aluminium contruction" means the whole boat, eg something
like a stryker, start being very careful, throwing a handful of copper
into the bilge or fitting a bronze skinfitting can destroy the hull.
my objection to the current trend is that materials are chosen for
their visual appeal, not their suitability for the task in hand.
if the aerial is aluminium, whi not simply make up and aluminium
bracket to mount it on?
rubber seals work very well to avoid water ingress
anodising is cheap, simple, and gives an astonishingly tough and
protective surface finish.
choose the fasteners wisely, and always watch out for "gotchas" like
copper based thread lubes to do a job that could be done by (plain)
grease or tallow.
here's a list of metals, starting from the corroded / anodic / least
noble end, working down to the cathodic end, you'll see that the
chromes and 2xx series stainless which are used in boats cos they are
shiney are some of the worst metals you could choose, you'll also see
"it's made of aluminium I reckon" isn't good enough if you take the
subject seriously.
HTH etc
MAGNESIUM
MAGNESIUM ALLOYS
ZINC
ALUMINUM 5052, 3004, 3003, 1100, 6053
CADMIUM
ALUMINUM 2117, 2017, 2024
MILD STEEL (1018), WROUGHT IRON
CAST IRON, LOW ALLOY HIGH STRENGTH STEEL
CHROME IRON (ACTIVE)
STAINLESS STEEL, 430 SERIES (ACTIVE)
302, 303, 321, 347, 410,416, STAINLESS STEEL (ACTIVE)
NI - RESIST
316, 317, STAINLESS STEEL (ACTIVE)
CARPENTER 20CB-3 STAINLESS (ACTIVE)
ALUMINUM BRONZE (CA 687)
HASTELLOY C (ACTIVE) INCONEL 625 (ACTIVE) TITANIUM (ACTIVE)
LEAD - TIN SOLDERS
LEAD
TIN
INCONEL 600 (ACTIVE)
NICKEL (ACTIVE)
60 NI-15 CR (ACTIVE)
80 NI-20 CR (ACTIVE)
HASTELLOY B (ACTIVE)
BRASSES
COPPER (CA102)
MANGANESE BRONZE (CA 675), TIN BRONZE (CA903, 905)
SILICONE BRONZE
NICKEL SILVER
COPPER - NICKEL ALLOY 90-10
COPPER - NICKEL ALLOY 80-20
430 STAINLESS STEEL
NICKEL, ALUMINUM, BRONZE (CA 630, 632)
MONEL 400, K500
SILVER SOLDER
NICKEL (PASSIVE)
60 NI- 15 CR (PASSIVE)
INCONEL 600 (PASSIVE)
80 NI- 20 CR (PASSIVE)
CHROME IRON (PASSIVE)
302, 303, 304, 321, 347, STAINLESS STEEL (PASSIVE)
316, 317, STAINLESS STEEL (PASSIVE)
CARPENTER 20 CB-3 STAINLESS (PASSIVE), INCOLOY 825NICKEL - MOLYBDEUM -
CHROMIUM - IRON ALLOY (PASSIVE)
SILVER
TITANIUM (PASS.) HASTELLOY C & C276 (PASSIVE), INCONEL 625(PASS.)
GRAPHITE
ZIRCONIUM
GOLD
PLATINUM
Cliff
Honking big Aluminum bolts <G>. Same exact alloy & temper?
But what are you bolting it TO?
--
Cliff
Andrew VK3BFA
Its going to be bolted to an aluminium tube, projecting out of the top
of the steel tower. I got NO IDEA what grade of aluminium the aerial (A
HYGAIN TH3Mk3, for those interested) - the original fittings were
steel (of SOME sort) and it stood up well to nearly 20 years outside.
Strangely, some fitting are rusted real bad, others no sign of
corrosion...I got it, very secondhand, and all the nuts bolts plastic
bits need replacing. HYGAIN offer (or did - not sure now) a rebuilt kit
containg all these bits - its expedient...but was curious re the
electrolysis action between stainless steel and aluminium - would have
thought it was less of a problem than plain gal. steel fittings.....ah
well. live and learn (or get more confused, not really sure....
Andrew VK3BFA.
beav
<abl...@alphalink.com.au> wrote:
you have another problem: if the Al alloys are different, you'll
still get galvanic corrosion.
i think what the secondary poster didn't allude to is that if you want
to keep corrosion to a minimum, you have to religiously maintain the
parts clean and rinse then with fresh water at every opportunity.
salt water is its own conductive path. all you need is dissimilar
metals....
beav
>On Fri, 20 Jan 2006 07:27:20 GMT, Michael <gai...@frontiernet.net> wrote:
>
>>Joe788 wrote:
>>> Today I had a guy telling me that chrome does not stand up to the
>>> weather and environment of a boat that is used in salt water. Now we
>>> are not talking about a propeller here, but various chrome trinkets
>>> around the boat, such as wakeboard racks, speaker enclosures, shifter
>>> knobs, etc.
>>>
>>> I was under the impression that chrome was a pretty good coating for
>>> such applications, but did not want to argue for fear of jamming my
>>> foot in my mouth. I know this is a pretty resourceful group when it
>>> comes to random bits of manufacturing related information....(remember
>>> the 900 post thread about the corrosion on the Fadal toolchanger??) .
>>> So, does anybody know where to find any decent online reference
>>> material for chrome plating's resistance to a salt water environment? I
>>> searched around on Google for a few minutes, but could not find
>>> anything of relevance.
>>>
>>
>>One suggestion is Stainless Steel. It looks much like chrome, maybe you
>>saw SS instead?
>
> http://www.chromplate.com/flash_hard_chrome.html
>[
>Micro-Cracked Hard Chrome (Bright)
hard chrome is an engineering coating used on hydraulic cylinders, oil
drilling operations, etc... where you need extraordinary hardness. i
suppose you could use it for appearance sake, but its very expensive.
you mention microcracked chrome and you might be referring to the
chrome over bright nickel over satin nickel. (chrome over duplex
nickel) THAT might offer you some serious protection...
automobile manufacturers came up with this method in the late 80's as
a reproducible means of cutting down on car chrome failure from road
salt.
if i recalll the anti corrosion mechanism, the very slight dissimilar
potential difference between the two Ni plates and cracks in the
chrome caused any localized corrosion cells to peter out before the
corrosion runs wild under the whole Ni plate.
you'd need to find a plating shop that was set up for this, perhaps a
job shop that supports the auto industry.
>
>This type of hard chrome offers a number advantages over the standard Hard
>Chrome...
>
>Harder and more wear resistant (hardness appox. 1050-1150 Vickers or 70 Rockwell
>C).
>Offers better corrosion protection than standard hard chrome
>Brighter finish than hard chrome
>
>These extra qualities make this mirco cracked hard chrome ideally suited for use
>with hydraulic rams which may be operating in dirty environments, if dirt is
>liable to lodge in seals, less harm may be done to the ram. For wet or
>salt-water environments, an under coat of nickel plating provides a corrosion
>resistant layer, that extends the working life of the ram considerably.
>]
>[
>Special Note on Hard Chrome
>It is a common misconception that chrome plating provides corrosion protection.
>This is not the case, only slight protection is given. Hard Chrome is porous at
>the microscopic level, which can let moisture and chemicals through to attack
>the base material. If the item is to be used in a damp environment, or where
>water based inks are used on printing machines, a layer of Nickel plating is
>required, prior to hard chrome plating.
>]
>
> I'd think that any fasteners should be of the exact same surface material
hard to do...
>(or nonconductive plastics) (to avoid electrolytic corrosion) and that
>such should not be joined to other metals (or in contact with them).
it may not even need to be in contact. crack a chemistry book or
google up "salt bridge" or "conductive salt bridge". i'll leave that
exercise to you...
> I.E.: Use the same plating on any fasteners into a fiberglass boat hull,
>don't even think of it with Aluminum or steel.
> If this is a submerged application perhaps a sacrificial electrode
>could be used as well?
just keep everything extremely clean. way easier said than done.
Cliff
>but was curious re the
>electrolysis action between stainless steel and aluminium - would have
>thought it was less of a problem than plain gal. steel fittings
Both Stainless & Aluminum are protected by an oxide layer.
Aluminum Oxide dissolves in bases IIRC (see Draino).
Chromium Oxide in the case of Stainless IIRC. Did not
check to see what dissolves that <G>.
A chart of galvanic potentials was posted ... the closer two
things are on it the less the voltage to cause corrosion, usually.
But that depends on current too. More current ==> more
(bulk) corrosion. No current, no corrosion by this mechanism.
See electronegativity (fifth thing down on the left for each element):
http://www.physics.ohio-state.edu/~lvw/physics/bigpertable.jpg
http://www.tech.plym.ac.uk/sme/strc201/corrosion1.htm
http://www.efunda.com/materials/corrosion/electrochem_entry.cfm
What happens in alloys or things like Oxides is another matter
(and beyond my scope) <g>.
[
Mr. McGuire: I want to say one word to you. Just one word.
Benjamin: Yes, sir.
Mr. McGuire: Are you listening?
Benjamin: Yes, I am.
Mr. McGuire: Plastics.
]
- from "The Graduate"
--
Cliff
Cliff
>salt water is its own conductive path.
??
--
Cliff
Cliff
>it may not even need to be in contact. crack a chemistry book or
>google up "salt bridge" or "conductive salt bridge". i'll leave that
>exercise to you...
"Solid NaCl did not conduct electricity .." ?
--
Cliff
David R Brooks
> disclaimer - spent years as a marine engineer catering to the private
> yacht sector.
>
> bronze (various grades) - shiny and most suitable, will de zinc over
> time if not protected by sacrificial anodes if installed badly
>
applications for exactly that reason, no zinc to leach out.
Martin H. Eastburn
I have some Bronze portholes - big ones - that were under Salt water for almost 50 years.
One the equator at that. Only blemish is coral and dark brownish color. Beauty.
Old design faucet sets were brass and the seats went bad - due to the loss of zinc
with the chlorine in the water.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
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Brent Philion
Whats the difference?
And how do you flip them over between states?
I've had stainless practive peices here rust on me after welding and it
didnt make sense to me as to the diff
Mark Jones
Is bronze capable of exhibiting the effects of "tin pest?" (Tin Pest is where
tin "decomposes" when exposed to temperatures below freezing - do a google
search for more info.)
Mark Thorson
>
> Is bronze capable of exhibiting the effects of "tin pest?"
No, tin has to be rather pure to exhibit tin pest.
Tin alloys like solder and bronze do not exhibit
tin pest.
Andy Dingley
> Is bronze capable of exhibiting the effects of "tin pest?" (Tin Pest is where
>tin "decomposes" when exposed to temperatures below freezing
No - like most alloys, it stabilises the lattice against this. I think
you actually have to have quite pure tin before you can demonstrate it.
Napoleon's mistake was to specify those extra-shiny buttons for his
army.
beav
a salt bridge in chemsitry is a U shaped glass tube filled with NaCl
solution with gelatin plugs at either end of the U to hold the
solution in.
a real world slat bridge could be a simple as salt water sitting
between two dissimilar metals.
and "dissimilar" might be a simple as two different alloys of the same
metal.
beav
>On 20 Jan 2006 05:14:36 -0800, "Andrew VK3BFA" <abl...@alphalink.com.au> wrote:
>
>>but was curious re the
>>electrolysis action between stainless steel and aluminium - would have
>>thought it was less of a problem than plain gal. steel fittings
>
> Both Stainless & Aluminum are protected by an oxide layer.
> Aluminum Oxide dissolves in bases IIRC (see Draino).
> Chromium Oxide in the case of Stainless IIRC. Did not
>check to see what dissolves that <G>.
>
> A chart of galvanic potentials was posted ... the closer two
>things are on it the less the voltage to cause corrosion, usually.
> But that depends on current too. More current ==> more
>(bulk) corrosion. No current, no corrosion by this mechanism.
not that easy. thse are lab comparisons. the real world is, well,
"real".
the oxide coat on Al is physically very tough. chemically, its at the
mercy of its surroundings.
stainless is a whole differnt story.
there are several varieties of stainless. for instance, 400 series
contains enough iron to rust. 300 series, once passivated (soaked in
strong acid to dissolve out any surface acitve iron sites) is
extremely durable. that being said, in a chloride environment, iron
can "unpassivate" and spot.
and then, of course, there are things like aircraft alloys (hastelloy,
mulitmet, etc that are mainly nickel chrome alloys that are incredibly
durable. and incredibly expensive.
beav
see my first post response.
beav
<lion...@consolidated.net> wrote:
>Brass de zincs - dezincify - Bronze is Tin-Copper.
>
>I have some Bronze portholes - big ones - that were under Salt water for almost 50 years.
>One the equator at that. Only blemish is coral and dark brownish color. Beauty.
>
>Old design faucet sets were brass and the seats went bad - due to the loss of zinc
>with the chlorine in the water.
>
>Martin
that's why brass and bronze have ben used on ships since time
immemorial. oh. yeah. and that's why swabbies have been polishing
and buffing it for just as long.
its durable, but it needs to be cleaned all the time....
beav
<bre...@sympatico.ca> wrote:
>Active Versus passive Stainless?
>
>Whats the difference?
iron sites on active stainless can spot rust and act as corrosion
loci. the trick is to soak the 300 series stainless in hot strong
acid to dissolve out the iron hot spots.
>
>And how do you flip them over between states?
soak the part in hot strong acid to repassivate
>
>I've had stainless practive peices here rust on me after welding and it
>didnt make sense to me as to the diff
what alloy of stainless? 400 series is hardly stainless. if it was
300 series, it needed to be soaked in acid.
Cliff
--
Cliff
Brent Philion
how Strong an acid?
Sulphuric?
Hydrochloric?
Acetic?
And what the proper name for the process so i can figure out what i need
ot buy to do it safely within a home shop
Glenn Ashmore
my stainless welds. For basic passivating you just soak the part for a few
minutes but I have been doing some deep passivating using an adjustable DC
power supply. For smaller stuff I have a 5 gallon bucket and use a graphite
rod on the negative side. The result is not truly electropolishing because
my power supply is not that big and I don't use heat but it leaves a stain
free matt surface that buffs up very easily. Good test for your welding
ability too. When you grind down a weld the pits often get smeared over.
10 minutes in the Citrisurf at max amps will reveal any voids.
For big stuff like the welds on the bow pulpit I grind until the weld is
faired in and then have a paddle made of flattened 1" copper tube wrapped
in cotton gauze and soaked in Citrisurf. I just swab the weld slowly for
about 5 minutes with the power supply delivering about 2 amps and get
similar results.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Brent Philion" <bre...@sympatico.ca> wrote in message
news:%qbBf.7638$ve.1...@news20.bellglobal.com...
Martin H. Eastburn
the ocean - rusting the iron bolts out - but the bronze is beautiful.
The special alloy props - monsters - a pair that exposed at low tide - were shinny.
I heard not long ago that one was dismounted for transport back to Germany.
So it really depends on the quality of bronze. Some require help - others don't.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
peter_d...@hotmail.com
the formation of chromium-carbides when temperature is high enough.
This reduces the amount of free chromium (in the HAZ), so corrision
resistance reduces. The common accepted 'threshold' for stainless is
12% free chromium, IIRC. The 'more' stainless your steel is, the more
chromium it will have.
BTW, this is all austenitic SS I'm talking about; don't know off-hand
about martensitic or ferritic SS.
Wasn't the passivating a form of heattreating? I know that SS could be
heattreated to reduce stress, but don't know if it would improve
corrosion resistance; it might if the chromium carbides get back into
solution?
Peter.
Cliff
>I am using Citrisurf, a line of citric acid based passivating solutions on
>my stainless welds. For basic passivating you just soak the part for a few
>minutes but I have been doing some deep passivating using an adjustable DC
>power supply. For smaller stuff I have a 5 gallon bucket and use a graphite
>rod on the negative side. The result is not truly electropolishing because
>my power supply is not that big and I don't use heat but it leaves a stain
>free matt surface that buffs up very easily.
That buffing probably removes or scratches ....
--
Cliff
Cliff
<lion...@consolidated.net> wrote:
>Quality Naval Bronze doesn't need cleaning. As I stated, it sat under salt water -
>the ocean - rusting the iron bolts out - but the bronze is beautiful.
>
>The special alloy props - monsters - a pair that exposed at low tide - were shinny.
>I heard not long ago that one was dismounted for transport back to Germany.
>
>So it really depends on the quality of bronze. Some require help - others don't.
Copper is an anti-fouling agent.
Quite toxic to much marine life.
Which is why it's often used (or was?) in marine paints .... (NOT for use on
Aluminum).
--
Cliff
Glenn Ashmore
> Wasn't the passivating a form of heattreating? I know that SS could be
> heattreated to reduce stress, but don't know if it would improve
> corrosion resistance; it might if the chromium carbides get back into
> solution?
"Passivation" has two definitions. The first is the spontaneous formation
of a chromium oxide skin which protects the iron from corrosion. The second
is the process of treating the surface of stainless with a mild acid to
remove free iron molecules so the first definition can happen.
Actually you need to passivate after heat treating. Heat, especially
welding temps, makes the molecules in the alloy separate to a degree leaving
free iron molecules on the surface. A mild acid passivating bath removes
the free iron and exposes the chromium below it to oxygen to form the
protective chromium oxide skin. .
beav
<lion...@consolidated.net> wrote:
>Quality Naval Bronze doesn't need cleaning. As I stated, it sat under salt water -
>the ocean - rusting the iron bolts out - but the bronze is beautiful.
sounds like the iron galvanically protected the bronze.
>
>The special alloy props - monsters - a pair that exposed at low tide - were shinny.
>I heard not long ago that one was dismounted for transport back to Germany.
>
>So it really depends on the quality of bronze. Some require help - others don't.
>
>Martin
i was thinking more about brass and bronze that on the deck that would
see salt spray and gets spots of tarnish that need to be cared for...
beav
wrote:
>I am using Citrisurf, a line of citric acid based passivating solutions on
>my stainless welds. For basic passivating you just soak the part for a few
>minutes but I have been doing some deep passivating using an adjustable DC
>power supply. For smaller stuff I have a 5 gallon bucket and use a graphite
>rod on the negative side.
hmmm! i'd seen a new mil std for using citric acid, but i'd never
tried it out.
we'd use straight up HNO3 (i can't recall the baume..) with a pinch of
HCl, and let the part soak for 20 minutes.
once rinsed, we'd spray a dilute KMnO4 solution on the part. any dark
spots that we could visually spot would indicate that the part wasn't
done and it would go back into the passivating solution.
the dark spots are active Fe locations that haven't been dissolved
out.
at that conc of HNO3, very few parts would need to be retreated.
> The result is not truly electropolishing because
>my power supply is not that big and I don't use heat but it leaves a stain
>free matt surface that buffs up very easily.
electropolishing and passivating aren't the same thing.
> Good test for your welding
>ability too. When you grind down a weld the pits often get smeared over.
>10 minutes in the Citrisurf at max amps will reveal any voids.
hmmm! again... very neat.
>
>For big stuff like the welds on the bow pulpit I grind until the weld is
>faired in and then have a paddle made of flattened 1" copper tube wrapped
>in cotton gauze and soaked in Citrisurf. I just swab the weld slowly for
>about 5 minutes with the power supply delivering about 2 amps and get
>similar results.
brush passivating. even neater.
thanks. i learned something new today!
Glenn Ashmore
yawl I can definitely state that bronze DOES need cleaning. That boat had
10 bronze Dorade vents, 52 bronze hinges and latches and a bronze bow
fitting. And I had to polish every D#*%^! one of them once a week!
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:11380723...@sp6iad.superfeed.net...
Cliff
>Having spent two summers as a deck hand on an old classic 80' Herreshoff
>yawl I can definitely state that bronze DOES need cleaning. That boat had
>10 bronze Dorade vents, 52 bronze hinges and latches and a bronze bow
>fitting. And I had to polish every D#*%^! one of them once a week!
Blame the fastners & what they were fastened to?
Why not use a clear *insulating* plastic coating?
--
Cliff
Glenn Ashmore
vents are a big old chunk of bronze that sticks up a couple of feet above a
teak baffle box. If sea salt stays on it for any length of time it will
turn green.
Even the best clear plastic coating degrades in the constant UV. Seawater
gets under it and is then a real PITA to strip.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Cliff" <Clhu...@aol.com> wrote in message
news:ecpct1536d9blpuhe...@4ax.com...
Martin H. Eastburn
of copper put there by Paul Revere himself. The copper made the ship very fast.
Barnacles... didn't attach as they did to the wood ships of the time.
Coral seems to attach without problem - calcium carbonate layer as protection.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Martin H. Eastburn
is the official Naval Bronze. It is a very special alloy and is expensive.
I have several porthole assemblies (multi-layer) and one that is without the 1/2" thick glass.
I'm trying to find a spot for one or more here on the site and the blank one -
saving it for a special pour source of metal.
Martin H. Eastburn
the main difference - I was trying to find some matching bolts - or make them.
I think I'll stick to standard bronze or make my own from the spare materials.
A source of it is in Houston Tx. Specialist in custom metals.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
> Got nothing to do with the fasteners. They were bronze anyway. Dorade
> vents are a big old chunk of bronze that sticks up a couple of feet above a
> teak baffle box. If sea salt stays on it for any length of time it will
> turn green.
>
> Even the best clear plastic coating degrades in the constant UV. Seawater
> gets under it and is then a real PITA to strip.
>
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Glenn Ashmore
finest materal available at the time. Naval brass above the waterline and
nickel aluminum bronze on wetted surfaces.
Actually the proper name is naval BRASS (C485) because it is 59-62% copper,
1.2 -2.2% lead 1% tin and the balance ZINC. C464 has .2% lead and no tin.
In a true bronze the primary alloy metal is tin. While the small tin and
lead content in C485 do reduce corrosion they do not prevent it. The
advantage of naval brass is strength. The disadvantage is the high zinc
content. Emersed in seawater without a nearby sacreficial zinc naval brass
reduces to copper sponge as the zinc leaches out. For this reason most
underwater bronze parts, and especailly large propellers are made from
nickel aluminium bronze, manganese aluminium bronze and high tensile brass
("manganese bronze").
Brightly polished naval brass turns green very quickly if it is not
maintained. If you don't believe that naval brass turns green, disassemble a
high quality pump body sometime.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:11381508...@sp6iad.superfeed.net...
Martin H. Eastburn
I doubt that was used on this ship: Xprinz Eugen that was captured, used,
put at Bikini with our men and many other ships and then towed to Kwaj and sunk.
My guess is the Germans (Krup Arms IIRC) had a different alloy.
You keep saying it tarnishes and leaches - but his didn't. So the alloy
is different.
Looking this up on a supplier in Houston - there are a dozen alloys they
call in Naval Bronzes.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
> This boat, the Pananchera, was built for a Vanderbuilt in 1922 out of the
> finest materal available at the time. Naval brass above the waterline and
> nickel aluminum bronze on wetted surfaces.
>
> Actually the proper name is naval BRASS (C485) because it is 59-62% copper,
> 1.2 -2.2% lead 1% tin and the balance ZINC. C464 has .2% lead and no tin.
> In a true bronze the primary alloy metal is tin. While the small tin and
> lead content in C485 do reduce corrosion they do not prevent it. The
> advantage of naval brass is strength. The disadvantage is the high zinc
> content. Emersed in seawater without a nearby sacreficial zinc naval brass
> reduces to copper sponge as the zinc leaches out. For this reason most
> underwater bronze parts, and especailly large propellers are made from
> nickel aluminium bronze, manganese aluminium bronze and high tensile brass
> ("manganese bronze").
>
> Brightly polished naval brass turns green very quickly if it is not
> maintained. If you don't believe that naval brass turns green, disassemble a
> high quality pump body sometime.
>
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Glenn Ashmore
is nominally .7% lead. C48500 "high lead" is nominal 1.9% lead. The lead
controls the machinability. They are often incorrectly referred to as a
bronze but as all are more than 35% zinc chemically they are actually brass.
It got the name "naval" because it was used extensively by the British navy
for deck fittings due to its strength and color. It does oxidize to a green
color but the British navy had an infinite supply of swabbies to polish it.
In the early battleship era an attempt was made to used it in condensers
and heat exchangers but because of major dezincification failures it was
replaced with manganese bronze in the Dreadnought class. Unfortunately for
the Turkish navy the British didn't issue a recall notice on the two battle
ships built for them and both were disabled in WWI due to condenser
failures.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:11381603...@sp6iad.superfeed.net...
Cliff
>The advantage of naval brass is strength.
People think that the Iron Age provided great advantages over the
Bronze age.
Yet many Bronzes are stronger & harder than most Steels IIRC.
Now, about the next Pyramid ...
"Who signed us up for this club?"
http://www.legendarytoys.com/media/DV-40032-8.jpg
(Stolen from a Gary Larson "Far Side" cartoon I could not find online IIRC).
--
Cliff
Cliff
>Got nothing to do with the fasteners. They were bronze anyway.
Even a slightly different alloy ....
>Dorade
>vents are a big old chunk of bronze that sticks up a couple of feet above a
>teak baffle box. If sea salt stays on it for any length of time it will
>turn green.
>
>Even the best clear plastic coating degrades in the constant UV.
Many are well stabalized or unaffected.
Consider such things as a clear automotive topcoat.
>Seawater
>gets under it and is then a real PITA to strip.
Has to get under first I expect ... and THEN cause electrolytic
corrosion. And a thin layer should have a largish resistance to
ion/charge flow the other way ...
--
Cliff
Glenn Ashmore
A minor difference in alloy between the screws and the part might cause a
little corrosion in the area of the screw but not 18" away.
A marine clear coat that will last longer than two years is the holy grail
of the marine finish industry.
Glisten PC and VHT-Clear are the two top performers. While they are popular
with the classic car restorers neither will last in the marine environment
more than two seasons and require mechanical abrasion to remove. Then you
have to buff the part with cut and color compounds to get a surface that can
be polished.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Cliff" <Clhu...@aol.com> wrote in message
news:076et1pcbr3jlatmt...@4ax.com...
Cliff
>A marine clear coat that will last longer than two years is the holy grail
>of the marine finish industry.
Marine paint (not anti-fouling), probably plural component, minus
the pigments & fillers?
--
Cliff
Cliff
>We are not talking about galvanic corrosion here. Just plain old oxidation.
>A minor difference in alloy between the screws and the part might cause a
>little corrosion in the area of the screw but not 18" away.
I'd probably no be too certain of that, right off.
--
Cliff
Cliff
>A marine clear coat that will last longer than two years is the holy grail
>of the marine finish industry.
Hmm .. did you say "cheap" & "easy" too?
--
Cliff
Ned Simmons
peter_d...@hotmail.com says...
You've described carbide precipitation which leads to intergranular
corrosion, and is just one of several corrosion mechanisms in stainless
steels. Heating the weldment beyond the sensitization temperature, then
cooling quickly, will redissolve the precipitated chromium carbides. A
more common solution is to use the low carbon grades of SS (304L, 316L),
or in fussier applications, columbium or titanium stabilized alloys
(321, 347).
Passivation is the chemical process described in other posts.
Ned Simmons
Glenn Ashmore
urethane. The problem is even with UV stabilizers the pigment provides most
of the UV protection to the bond surface. A good two part LPU marine
finish will last 10-15 years with proper maintenance but when you remove the
pigment it degrades relatively quickly.
I have been studying this stuff for 7 years because I like the style of
bronze fittings and I can cast bronze to make some custom items like chocks
that fair into the cap rail but I can't cast stainless steel. I have had to
resign myself to 316L for custom weldments and just buy stock fittings for
the rest.
Which reminds me. The shop I have been using for electropolishing got tired
of dealing with the EPA and closed up. Anyone know of an electropolishing
shop in the southeast that will take on a small job without an outrageous
minimum charge?
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Cliff" <Clhu...@aol.com> wrote in message
news:ve1ft15glei05v1pb...@4ax.com...
Glenn Ashmore
seldom easy. :-)
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Cliff" <Clhu...@aol.com> wrote in message
news:rj1ft1dpce423vjs1...@4ax.com...
Kevin G. Rhoads
>HCl, and let the part soak for 20 minutes.
For repassivating stainlesses, nitric is often the old-time choice. But AFAIK anything
with chloride ion is deleterious to the passivating layer. THat's one of the reasons
that sea-water and food juices (often containing salt) are problematic. Cl- attack
can be reduced by adding Ni to the stainless mix, so the 18-8 for cooking (18% Cr, 8% Ni)
or 18-10 for the higher end stuff.
Just saute your stainless in a nice gently bubbling bath of nitric, and keep the stuff
OFF your skin.
Cliff
>The Glisten PC is an epoxy and I think the VHT is a two part
>urethane.
The later is more likely to have UV & IR problems IIRC. Blocking
& stabalizing agents can degrade/leach out/ etc. with time too in
somecases ... but perhaps a fresh coat before the 10 years is
up?
OTH The later should probably be more abrasion resistant ...
--
Cliff
Martin H. Eastburn
are brassy - or yellowish or reddish in color. I don't recall a spec of green.
Remember this was held at the equator /date zone ocean for 50 years. It should
be darkish green or pale green. But not green. The running lights I have are.
They don't have the same metal content - look brass like.
Since this was WW II - and a super Dreadnought - remember sister ship to the
Bismark that broke out of the blockade. The Prinz was ordered not to follow
the Bismark once it was damaged by the bomb attack by a Bi-Plane on the rudder.
(The state of the art fighter-bombers didn't have enough impact.) The Bismark
was of movie and very high drama time in life. National honors were on the line.
The Prinz was ordered to the Pacific to join up with the Japanese. I don't think
it made it - not sure when it was taken. Maybe not in war footing. Might have
been in port - South America was getting new population at the time ?
Without taking this to a mass spec machine we will likely not know.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
> There are three types of naval brass. C465 is lead free. C483 "medium lead"
> is nominally .7% lead. C48500 "high lead" is nominal 1.9% lead. The lead
> controls the machinability. They are often incorrectly referred to as a
> bronze but as all are more than 35% zinc chemically they are actually brass.
>
> It got the name "naval" because it was used extensively by the British navy
> for deck fittings due to its strength and color. It does oxidize to a green
> color but the British navy had an infinite supply of swabbies to polish it.
> In the early battleship era an attempt was made to used it in condensers
> and heat exchangers but because of major dezincification failures it was
> replaced with manganese bronze in the Dreadnought class. Unfortunately for
> the Turkish navy the British didn't issue a recall notice on the two battle
> ships built for them and both were disabled in WWI due to condenser
> failures.
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Martin H. Eastburn
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Glenn Ashmore
has been cleaned off or not naval brass. (Because the primary alloy metals
are copper and zinc, technically there is no such thing as "Naval bronze".
The confusion comes because of the small amount of tin.) It is possible to
clean off the green without removing the brown patina. Here is what fresh
naval brass looks like.
http://users.eastlink.ca/~jbentley/GoldenEngine.html
As it weathers without any maintenance it turns a medium dark brown usually
with powdery green corrosion streaks. If you go to the construction page of
that site and scroll down you can see what a weathered piece looks like.
The problem is on classic yachts you don't want it to turn brown or green so
you polish it regularly. Older work boats don't care about the brown but
they usually don't want the green. Green fittings are an indication of a
poorly maintained boat
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Glenn Ashmore" <gash...@cox.net> wrote in message
news:jADBf.13617$Dh.1696@dukeread04...
Glenn Ashmore
brass. Makes the one I made from regular Stuart castings look like a hack
job.
Martin H. Eastburn
in the ME shops. That was fun! I'll look at the portholes in the A.M. - out in
the shop - the glass is maybe 12 or more inches wide. Main frame bracket with the
swing window. There was one cover that was on another, but was destroyed by movers
during one move with Dads stuff. Such is life.
Each pair must be 50# or so in weight.
I never remembered seeing any green - maybe there is somewhere.
I still don't know why copper, tin, lead or copper, tin, zinc is brass.
Those are leaded bronze to me.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
> If it is dark brown it is either just on the surface and the green corrosion
> has been cleaned off or not naval brass. (Because the primary alloy metals
> are copper and zinc, technically there is no such thing as "Naval bronze".
> The confusion comes because of the small amount of tin.) It is possible to
> clean off the green without removing the brown patina. Here is what fresh
> naval brass looks like.
> http://users.eastlink.ca/~jbentley/GoldenEngine.html
>
> As it weathers without any maintenance it turns a medium dark brown usually
> with powdery green corrosion streaks. If you go to the construction page of
> that site and scroll down you can see what a weathered piece looks like.
>
> The problem is on classic yachts you don't want it to turn brown or green so
> you polish it regularly. Older work boats don't care about the brown but
> they usually don't want the green. Green fittings are an indication of a
> poorly maintained boat
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Cliff
<lion...@consolidated.net> wrote:
>Without taking this to a mass spec machine we will likely not know.
Borax beads & flame tests?
Might at least tell you which elements are alloyed.
Compare beads & flames with same from a known alloy
& guess the % of each?
--
Cliff
Cliff
>Glenn Ashmore
>
>I'm building a 45' cutter in strip/composite. Watch my progress (or lack
>there of) at: http://www.rutuonline.com
>Shameless Commercial Division: http://www.spade-anchor-us.com
IIRC A bit back you were saving up for as specific alloy per your Site.
As I recall it that alloy needed Antimony. Why not alloy your own
to cast from the cheaper things you can readily get?
--
Cliff
Glenn Ashmore
> Those are leaded bronze to me.
>
A few basics about brass and bronze.
When the primary components are copper and zinc it is a brass regardless of
any trace modifiers like tin and lead. The type of brass is normally
determined by the amount of zinc.
When the primary components are copper and some other metal it is a bronze.
Again regardless of the modifiers. The type of bronze is determined by the
metal primarily alloyed with the copper and include silicon, manganese,
aluminum and others. Some bronzes are named for the trace modifiers like
phosphorus . Many bronzes may contain tin and zinc but the primary metal is
tin.
There are several brasses that are commonly called bronze because they
contain small amounts of tin. Naval bronze being one of them. Similarly
there are bronzes that are referred to as brass. Red brass or gunmetal is
actually 88% copper, 10% tin, 2% zinc and is therefore a bronze.
To complicate the naval brass issue there is "Navy" bronze which actually is
bronze. Naval M bronze (C922) is 6% tin and 4.5% zinc.
Martin H. Eastburn
Yep - I know - now I have to generate a bunch of versions. Should run it up
to my University - visit and ask for ID. Or run it over to the other University
where I was in masters area - but liked their Physics R&D area - or send it to SLAC
were I was a visitor for a number of times.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Martin H. Eastburn
I'm not concerned with all of these suppliers and foundries with false information.
I was in the shop long enough to check mail and grab a level.
I'll take another look later.
I guess if I melt down the not prime one - the zinc will likely evaporate
and change the alloy. Well time will tell.
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
>>I still don't know why copper, tin, lead or copper, tin, zinc is brass.
>> Those are leaded bronze to me.
>>
>
>
> A few basics about brass and bronze.
>
> When the primary components are copper and zinc it is a brass regardless of
> any trace modifiers like tin and lead. The type of brass is normally
> determined by the amount of zinc.
>
> When the primary components are copper and some other metal it is a bronze.
> Again regardless of the modifiers. The type of bronze is determined by the
> metal primarily alloyed with the copper and include silicon, manganese,
> aluminum and others. Some bronzes are named for the trace modifiers like
> phosphorus . Many bronzes may contain tin and zinc but the primary metal is
> tin.
>
> There are several brasses that are commonly called bronze because they
> contain small amounts of tin. Naval bronze being one of them. Similarly
> there are bronzes that are referred to as brass. Red brass or gunmetal is
> actually 88% copper, 10% tin, 2% zinc and is therefore a bronze.
>
> To complicate the naval brass issue there is "Navy" bronze which actually is
> bronze. Naval M bronze (C922) is 6% tin and 4.5% zinc.
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Martin H. Eastburn
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Autymn D. C.
stabalizing -> stablising
abrasion resistant -> abrasion-resistant
no -> not
Martin H. Eastburn
Fancy one is from - you know gold braid types - One I think I might be able to
get through!
They did have some tarnish - green - not much and not a coverage thing.
So I know it is a copper based metal at least.
Looking in my "Metals Handbook - page 513 - propose C44500 Admiralty, Phosphorized .02-.1 P.
called a "Tin Brass" - more tin. 70-73 cu, .07 pb .06 Fe .8-1.2 Sn .02-.1 P balance Zn.
The only reason it is called a brass and not a bronze - is the unknown amount of zinc.
Or it is in the something else - I think the names are simply a game.
Copper-silicon alloys (Silicon Bronzes) contain tin and zinc!
SO likely it is by application or by common use is used in the
classification of the copper and copper alloys.
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
Glenn Ashmore wrote:
>>I still don't know why copper, tin, lead or copper, tin, zinc is brass.
>> Those are leaded bronze to me.
>>
>
>
> A few basics about brass and bronze.
>
> When the primary components are copper and zinc it is a brass regardless of
> any trace modifiers like tin and lead. The type of brass is normally
> determined by the amount of zinc.
>
> When the primary components are copper and some other metal it is a bronze.
> Again regardless of the modifiers. The type of bronze is determined by the
> metal primarily alloyed with the copper and include silicon, manganese,
> aluminum and others. Some bronzes are named for the trace modifiers like
> phosphorus . Many bronzes may contain tin and zinc but the primary metal is
> tin.
>
> There are several brasses that are commonly called bronze because they
> contain small amounts of tin. Naval bronze being one of them. Similarly
> there are bronzes that are referred to as brass. Red brass or gunmetal is
> actually 88% copper, 10% tin, 2% zinc and is therefore a bronze.
>
> To complicate the naval brass issue there is "Navy" bronze which actually is
> bronze. Naval M bronze (C922) is 6% tin and 4.5% zinc.
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Glenn Ashmore
Normally you refer to the amount of primary alloying metal as "balance"
because the other components may vary within limits. In the example of
Phosphorized admiralty brass the total of the copper other components can
vary from 70.95% to 74.5% so the zinc will vary from 29.05% to 25.5%. There
is a minimum of 25 times more zinc in it than tin so it is properly a brass.
The confusion between brass and bronze is something you have to watch out
for when buying copper alloys for a corrosive environment. It is surprising
how many metal salesmen don't know the difference.
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:1138415...@sp6iad.superfeed.net...